WO2008/068728 A1 describes a light source having a plurality of light elements and a plurality of light element controllers, each connected to a respective light element. The light source comprises a bus interface, which is connected via a light source bus to several light element controllers. The light source bus is set in a broadcasting mode. The bus interface broadcasts a general command, typically including overall light settings for the light elements, to the light element controllers. Each light element controller has a capability of calculating specific drive signal data for the light element to which it is connected.